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Guide to Pressing Seaweed: Introduction
Step 6: Press  Click here to buy the printed booklet version
Weigh down your press with weights....
Put your assembled press under pressure with weights, straps, or clamps. If using weights, first move your press to a spot (often the floor) where it can remain for a few days next to a blowing fan. Stack books, cinder blocks, buckets full of sand, or anything else that is heavy (but light enough to move without hurting yourself) on top of your press. Generally, the more weight the better, but be certain that the weight is evenly distributed and stable. If you are pressing fleshy specimens and using an open-mesh covering sheet (such as cheesecloth), you may want to begin with relatively little weight, then increase the weight after a day of drying: this helps to prevent specimens from being embossed with the pattern of the mesh covering sheet. Twenty pounds (9 kg) is a reasonable minimum for a standard 12 18 inch (30 46 cm) press, with more weight required for larger presses and less for smaller.
...or compress it with straps or clamps
If you are using straps or clamps, do your best to get them as tight as possible, again making certain that the pressure from them is evenly spread across the press. Four clamps or two straps are needed for a standard-sized press.
Use a fan to help dry the press
If available, use a fan to help dry your specimens. Place the fan between 1 and 3 feet (30-90 cm) away from your press, directly facing one of the sides with open channels in the corrugated cardboard. These sides are usually, and preferably, the long sides of your press. Your goal is to blow a steady stream of air through every channel in all the sheets of corrugated cardboard. Turn the fan on 'high', check the aim of the airflow with your hand on the far side of the press, and reposition the fan until you can feel air moving through every part of the press. With a small fan on high, many delicate seaweeds will dry overnight, and coarse seaweeds should be dry within a few days. If attended regularly (next step below), presses will dry adequately without a fan, but this can take up to a week. If you are not using a fan, try to keep your press in a place with warm dry air, such as safely above a small heater. Commercial drying cabinets are also available, but these don't necessarily offer advantages over a fan unless you are drying hundreds of specimens at a time.
Check the press daily and change the blotting paper as needed
Open the press after several hours or overnight and replace any damp blotter between specimens with clean dry blotter. Then reseal the press and set it up to dry again. You can feel with your hand to try to gauge if the blotter is wet or dry. If you find damp sheets of cardboard, replace them as well. You should expect to change the blotter daily for several days if you are pressing any coarse specimens or drying the press without a fan. If you are using a fan, don't forget to turn it off before opening your press, and take care as always when unstacking and restacking your press. As you go, remove any pressed specimens that are completely dry (you may need to carefully peel back the cheesecloth/covering sheet to test for dryness), but try to resist the urge to peek at damp specimens, which might be disturbed if exposed at this point. Each time you change blotter, also consider reloading the wet blotter and ventilators in the top of the press to expedite their drying, but be certain that they are substantially separated from your specimens. Alternatively, you can dry damp blotter in a second press, or simply spread out. The faster you can dry your specimens, the less blotter you will need, and the less chance that any of your work or materials will become moldy.
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